This invention relates to gas springs for use in articles such as chairs, beds or the like, and particularly, to a gas spring of the type having an actuating device for adjusting the overall length of the gas spring to adjust the height of the chairs or beds.
Usually, the main body portion of gas spring is mounted on a supported member such as a seat portion of a chair and a piston rod of the gas spring is mounted on or engages with a supporting member such as a base portion of the chair, and the actuating device is mounted on the supported member separately from the gas spring. A valve actuated by the actuating device is mounted directly on the main body portion of the gas spring with an actuated end projecting outward of the main body portion for engaging with an actuating end of the actuating device.
Thus, since the main body of the gas spring and the actuating device are mounted separately on the supported member, it has been difficult to obtain a proper alignment therebetween and to obtain a proper relative position between the actuating end of the actuating device and the actuated end of the valve. When the actuating device and the actuated end such as a projecting end of a valve stem are not aligned properly or are positioned offset relative to the direction of the movement of the valve, either or both of the valve and the actuating device will wear unevenly and slantingly during a long period of use thereby causing a bending force on the valve or a lever of the actuating device and resulting operational failure. When a proper relative position is not attained between the projecting end of the valve and the actuating end of the actuating device, a desired stroke of the valve will not be attained by operating the actuating device. It is possible to avert the aforesaid shortcomings by providing some adjusting devices in mounting the actuating device or the gas spring, but such adjusting devices are complicated in construction and expensive.
Usually a bracket is attached on the supported member for mounting the gas spring thereon, and thus it is possible to utilize the bracket for mounting the actuating device, but, the construction of the bracket is complicated and the length of the bracket is increased to mount the actuating deivce.